A fluid dynamic bearing device of this type can be suitably used in a small motor such as a spindle motor for an information apparatus such as a magnetic disk drive like an HDD, an optical disk drive for a CD-ROM, CD-R/RW, DVD-ROM/RAM or the like, or a magneto-optical disk drive for an MD, MO or the like, as a polygon scanner motor of a laser beam printer (LBP), as a motor for a projector color wheel, or as a fan motor used in an electrical apparatus or the like.
In many of conventional fluid dynamic bearing devices, a bearing sleeve is fixed to an inner periphery of a housing, and a shaft member is inserted into an inner periphery of the bearing sleeve so that a radial bearing gap is formed between an outer peripheral surface of the shaft member and an inner peripheral surface of the bearing sleeve. By means of a dynamic pressure effect of a lubricatine fluid, which is generated in the radial bearing gap, the shaft member is rotatably supported.
In recent years, for the purpose of cost reduction and the like involved with reduction in the number of components, it has been proposed that the bearing sleeve and the housing are integrated with each other and replaced with a die-molded product (Patent. Document 1).    Patent Document 1: JP 2006-226520 A